1. Field of the Invention
In general, the present invention relates to food presses that are used to compress food into various shapes. More particularly, the present invention relates to the hydraulic drive mechanisms of food presses that cause molds to press against food in order to reshape the food.
2. Prior Art Description
Animals of each species come in a variety of shapes and sizes. The variety in size and shape of an animal can have many causes, such as the animal's age, sex, muscle tone, and diet. As a consequence, the cuts of meat from the same parts of two animals are never identical in weight, density, fat content, shape and/or size.
In the meat industry, some cuts of meat are expected to have a relatively standard shape. A good example of such a cut of meat is bacon. Bacon is a cured meat prepared from pork. Bacon can be prepared from several different cuts of pork. In different regions of the world, bacon is produced from the side and/or back cuts of pork. However, in the United States, bacon is primarily made from pork belly. Outside of the United States, pork belly bacon is often referred to as “streaky bacon”, “fatty bacon”, or “American style bacon”.
In the United States, most consumers buy bacon at a retail grocery store. In the grocery store, the bacon is prepackaged and pre-sliced into strips. Within the packaging, retailer consumers expect the slices of bacon to be generally uniform in length, height and thickness.
If a pork belly were just to be sliced into bacon strips, the bacon strips would vary greatly in length and height. Furthermore, much of the meat on the pork belly would be wasted because it would be cut into dimensions that are too small to serve as bacon strips. As a result, it is common for meat packers to reshape pork bellies before they are cut into bacon strips. In this manner, most all of the pork belly can be cut into acceptable bacon strips.
To shape pork bellies into bacon, the pork bellies are often set into a machine press. Molds are forced against the meat under the force of hydraulic pistons. The result is that the meat conforms to the shapes of the mold. Consequently, sections of the meat that are too thick are pressed thinner, while thin sections of the meat are made larger. The result is that each piece of meat leaving the machine press has uniform dimensions. Such prior art meat pressing machines are exemplified by U.S. Pat. No. 3,759,170 to Bettcher, entitled Food Press.
Prior art meat pressing machines, however, do have some disadvantages. Most prior art meat presses compress a piece of meat with only linear compression forces. That is, the top surface of the meat is pressed directly toward the bottom surface of the meat. The two ends of the piece of meat are pressed toward each other. This extrudes the meat into the shape of the molds. However, the direct linear compression of the meat can cause the meat to ripple as it extrudes within the mold. Furthermore, the direct linear compression can cause lines between fat and meat to separate as the meat shears under the compression forces. Both effects can ruin a slab of meat, causing the misshaped slab of meat to be used as scrap.
A secondary concern in compressing a slab of meat with linear forces, is that a great deal of pressure is required to change the shape of meat under simple compression. As such, meat presses must be made to be very powerful. The meat presses, therefore, require a substantial amount of energy to run. The more energy it costs to shape a slab of meat, the more expensive that slab of meat becomes at market.
Yet another problem associated with many prior art meat presses is that the molds used in the presses can only be used on slabs of meat that are between a predetermined minimum size and maximum size. If a slab of meat is encountered that is outside the acceptable range, then the molds within the meat press must be changed. For example, the molds on a prior art meat press may be able to shape a slab of meat between seven and ten pounds. However, if a twelve pound slab is provided, the molds must be changed to compensate for the larger slab of meat. If a slab of meat is placed in a mold of the wrong size, it will either fail to be formed properly or will be squashed into scrap.
A need therefore exists for an improved meat press that can compress a slab of meat with complex, non-linear forces, so as to cause less damage to slabs of meat. A need also exists for an improved meat press that can automatically adjust to slabs of meat of different sizes without requiring the molds of the press be changed.
Lastly, a need also exists for a meat press that can shape slabs of meat using less energy. In this manner, the meat press is more efficient, thereby reducing the cost of processing the slab of meat.
These needs are met by the present invention as described and claimed below.